Arylsulfamyl benzoic acids



Patented Aug. 26, 1952 ARYLSULFAMYL BENZOIC ACIDS James M. Sprague,Drexel Hill, and Charles S. Miller, Prospect Park, Pa., assignors toSharp & Dohme, Incorporated, Philadelphia, Pa., a

corporation of Maryland Application August 20, 1949, Serial No. 111,583

4 Claims. (01. 167-55) No Drawing.

This inventionrelates to sulfamylbenzoic acids which are effective asadjuvants for use in conjunction with the administration of penicillinto provide an increase in the blood plasma penicillin concentration witha given dose of penicillin,

thereby making possible very high penicillin blood levels, or permittingthe use of smaller quantities of penicillin for providing a given bloodlevel,

or permitting the less frequent administration of penicillin'whilemaintaining a penicillin blood level adequate for bactericidal orbacteriostatic purposes. This invention also relates to the preparationof various dosage forms in which one or more of the new compounds areincorporated for administration by various routes.

Penicillin today is a well established therapeutic agent used in thetreatment of bacterial, in particular, coccus infections. For internaluse, it is commonly administered intravenously, or intramuscularly, ororally. When high blood levels are required intravenous administrationor administration by continuous venoclysis, is

used. r

The major cause of the difficulties involved in attempting to maintainadequate or high penicillin blood levels follows from the fact thatsubstantially all of the penicillin in the blood is removed in a singlecirculation through the kidneys.

Penicillin appears to be almost quantitatively excreted from the bloodby the epithelial cells of the tubules, at least within plasma concentrations which have been explored, with the result that its rate ofexcretion from the blood stream is approximately five times that ofmaterials which are excreted by glomerular filtration alone, the tubularexcretion accounting for about 80 (81)% and the glomeruli about 20(19)%.

Various proposals have been made to overcome the difliculties due to therapid elimination of penicillin, such as the administration'of it insuspension in an oleagenous material, the mixture being administered byintramuscular injection. While this proposal is effectivein prolongingthe time interval between injections, its disadvantage is that thepenicillin is still excreted almost quantitatively when the blood passesthrough the renal system, and therefore does not permit the maintenanceof high blood levels nor does it permit the use of smaller quantities ofpenicillin to obtain a given blood level.

The second proposal which has been made to provide for the reduction inthe rate of excretion of penicillin has been to use, in conjunction withit, a material which, like penicillin, is selectively 2 excreted by thetubules. By having the ratio of the added agent to the penicillinsufliciently large, this concept provides for a substantial reduction,in the rate of excretion of penicillin by the tubules and thus slowsdown its removal to a substantial extent. Various agents includingdiodrast and hippuric acid, or derivatives or precursors thereof,havebeen proposed or used for this purpose. Such agents do not, however,seem to afford a solution to the problem of value except in extremecases, because as the reduction in the rate of penicillin excretion isa, reflection of the degree of overloading of thetubules with materialswhich they function to, remove from the blood, it is necessary tomaintain a very high concentration of the agent in the blood stream toafford a. favorable partition ratio between the agent and thepenicillin, and, in addition, because the agents are themselves rapidlyremoved from the blood stream, it is necessary to administer them inlarge quantities to maintain the neces sary high plasma concentrations;This presents an additional problem since in order to maintain the highconcentration of theseagents theymust be administered intravenously asthey are not well absorbed from the gastroq-intestinal tract.

The present invention is based upon the discovery that removal .ofpenicillin from the blood stream by the kidney tubules can beeffectively blocked by the adjuvants of this invention, having thegeneral formula? The sulfamylbenzoic acids ofthe'invention arerelatively non-toxic, they are soluble in blood plasma and operate, whencarried by the blood stream'into contact'withthe tubules, to preventtheir normal action in removing penicillin from the blood streamfr.The'adjuvants themselves are not excreted to any substantial extent bythe tu-,

. injection by this route impractical.

bules, and the available evidence indicates that on coming into contactwith the epithelial cells of the tubules, they operate to block theiraction by interference with the normal functioning of the epithelialcells and do not inhibit the excretion of the penicillin by competingwith it within the tubular functional capacity. Thus, the adjuvants areeffective in eliminating or very radically reducing tubular excretion ofpenicillin in plasma concentrations around 10 mg. per 100 cc., which isabout the threshhold value for agents such as p-aminohippuric acid ordiodrast which inhibit tubular penicillin excretion by competition forthe available tubular excretion capacity. The highly effective adjuvantsof this invention will reduce the excretion of penicillin by thetubules, at a blood plasma concentration of about 10 mg. per 100 cc. toalmost zero, so that the actual elimination of penicillin from the bloodstream becomes substantially that resulting from glomerular filtration,that is, aboutone-fifth. the normal rate (ignoring plasma binding) Theadjuvants are also eliminated by the glomeruli.

The adjuvants may be administered orally or,

when dissolved in an aqueous solution, they may be administeredintravenously or intramuscularly. This last method has not yet provendesirable for single injection of the material, because in general,administration of more than 2 cc; per

singleinjection intramuscularly is inadvisable,

and the quantities of adjuvant desirable to use, i. e-., 4 to 16 gramsper day, are such. as to make However, the sulfamylbenzoic. acids ortheir salts are well adapted for continuous intramuscular orsubcutaneous clysis.

In general, oral administration of the adjuvants at the rate of 4 to 16grams per day is adequate to suppress the rate of penicillin excretionto an extent such that the blood level with a given dose of penicillinadministered orally or intramuscularly in aqueous solution will beincreased to as much. as four times the level. obtained without the useof the adjuvant, and will permit either the use of a very muchsmallerquantity of penicillin: to provide a given blood level, for example,permitting the penicillin doses to be about one-fourth of those commonlyused, or permitting the provision of penicillin blood levels severaltimes as great. as thosefobtainable with the administration of.penicillin by the routes ordinarily used today.

The adjuvants of the invention or a suitable salt of any one of them maybe administered in admixture with the penicillin, or separatelytherefrom. In any event, whether the adjuvant is administered inadmixture with or separately from the penicillin, the quantity usedshould be such as to provide a concentration in the blood stream ofadjuvant adequate to block substantially the excretory mechanism of thetubules. Maximum effect will be obtained with blood plasmaconcentrations of about 5 to 15 mg. per

100 cc., obtainable at dosage levels of about 4,

to 16 grams per day'orallyand somewhat less than this intravenously.

The adjuvants maybe prepared in any convenient dosage form, either aloneor admixed with penicillin, such as in a compresed tablet, a dry filledcapsule, or a soft elastic capsule. It is to be understood, of course,that other ingredients such as binders, diluents, excipients, antacidsubstances, or'other inert or therapeutically active compounds may beincorporated into, any selected. dosage form. alongwith the adju vant oradjuvant plus penicillin, provided the added ingredient does not destroythe activity of either the adjuvant or penicillin; Similarly, theadjuvant and, if desired, the penicillin, may be dispersed in anoleagenous base either alone or along with other suitable substances andfilled into soft elastic capsules or an aqueous solution may be preparedand filled into ampuls. Other suitable dosage forms will be readilyapparent to those skilled inthe art, and it is not the purpose of thisdiscussion to limit the mode of packag- The new sulfamylbenzoic acidcompounds of;

r the invention are advantageously inade by react-- ingpara-carboxybenzenesulfonyl halide with nitroaniline, preferably in thepresence of an excess, e. g., a 2-3 molar excess, of the nitroaniline,and advantageously in the presence of an inert solvent, such as acetone;followed, if desired, by reduction of the resultingpara-'(nitrophenylsulfamyl) -benzoic acid to the corresponding amine.The adjuvants of this invention may also be obtained by (I) reactingpara-carboxybena zene-sulfonyl halide with phenylenediamine di--hydrochloride, preferably in the presence of. a solvent, such asacetone, and in the presence of aqueous alkali, e. g, an aqueous:solution of so dium hydroxide, or (2) by reacting paraetoluene sulfonylhalide with nitroaniline in an inert solvent, such as pyridineandoxidizing the para (nitrophenylsulfamyl) -toluene thus. obtained topara-(nitro-phenylsulfamyl) benzoic acid, and, if desired, reducing thenitro tor the: amino group.

The ortho-sulfamylb'enzoic acid. derivatives may be prepared. byreacting saccharin with. the nitroor amino-phenyl halide, and treating.the product thllS. formed, with. an alkali metal also-- holate. 1

. The meta-sulfamyl' benzoic'acid derivative may be prepared by reactingmeta-sulfo-benzoyldichloride with an alcohol, e. g., methanol, addingthe product thus formed to the nitroor amine phenylhalide, preferablydissolved. in a solvent,

. thereby obtaining. alkyl. meta-nitroror amino.

phenylsulfamyl) -.b'enzoate. The ester is uneasy-- drolyzed to thecorresponding benzoic acid d'e' obtained by any one of the abovermethodsmay be alkylated by'knownmethods,suchias by'reacting thearylsulfamylbenzo-ic acidwith. an alkyl halide.

The preparation of" the compoundsof the invention is illustrated by, butnot restricted to, the following examples:

Para (meta--aminophenylsitlfamyly benzoi'c acid-To a solution of 27.6 g.(0.2.mole) of m.- nitroaniline in l0 0icc..drypyridine', ll-.8; g; (10%excess) of p-toluene-sulfonyl' chloride was added in portionswithstirring; 'Considerableheat was evolved, andwhen this had. subsided.the flask' was warmed on'a hot plate for about one-half hour. Thereaction mixture wascooled andthen poured into approximately 500cc.dilute: hydro chloricv acid with stirring), Anr oil; separated whichsolidified onrfurther 'stirring,.yielding. 5719i g., quantitative yield,of para-(meta-aminophenylsulfamyD-toluene, melting at 134-5.

A suspension was prepared from 85 cc. of water, 27.4 g- (0.094 mole)para-(meta-nitrophenylsulfamyD-toluene and 37.7 g. (0.127 mole) ofsodium dichromate dihydrate. 93.5 g. of concentrated sulfuric acid wasadded dropwise with stirring over a half-hour period. The temperaturewas raised to 100 and maintained at 100- 115 for one hour. Aftercooling, the mixture was diluted with 250 cc. of water and the mixturefiltered. The solid residue was treated with excess aqueous sodiumbicarbonate solution and the insoluble material filtered, yielding 18.83g. of the para-(meta-nitrophenylsulfamyl) -toluene starting material,melting at 1334. The bicarbonate filtrate was treated with charcoal and6 coal and reprecipltated by neutralizing the solution with sodiumhydroxide. 11.92 grams (61% yield) of theproductwas obtained, which,upon recrystallization from 50% alcohol, yielded 8.36

grams of. para (meta aminophenylsulfamyl) Table a j ticiitii I ToxicityAdluvam lnfll V Adminis Coadminisin Dogs 1 a tered tered Dose" CIYSS,without with Ins/kg Adjnvan-t Adjuvant msm-Oooon ]& 30.0 25.0 3.03 1. 22o 1 NH,

1 In all experiments, the calculated dose of penicillin was 10,000 unitsinitially followed immediately by a venoclysis of penicillin at a rateof 125 units per minute. l

2 Initial dose given at the time the constant intravenous infusion(venoclysis) of the adjuvant was begun. The initial dose wasadministered intravenously unless otherwise noted.

3 Expressed as a multiple of the amount that was calculated as beingfiltered at the glomerulus, uncorrected for plasma protein binding ofpenicillin. ,(Control phase of experiment.)

4 Same as 3, but following the coadministration of the adjuvant. i

5 0=not toxic to dogs in the dosage administered in these experiments.

the soluble material precipitated by acidification with dilutehydrochloric acid, yielding 4.32 g. of para-(meta nitrophenylsulfamyl)-benzoic acid, melting at 235 with decomposition. Similar resuits wereobtained when p-(m-nitrophenylsulfamyl) -toluene was oxidized inalkaline permanganate.

To a solution of 33.1 g. (0.24 mole) of m-nitroaniline in 150 cc. ofacetone 17.7 g. (0.08 mole) of p-carboxybenzenesulfonyl chloride wasadded, in portions with stirring. When solution was complete the acetonewas evaporated on a steambath. The residue was treated with excessaqueous sodium bicarbonate solution and the insoluble residue filteredoff. The filtrate was treated with charcoal and the product precipitatedwith dilute hydrochloric acid, yielding 21.7 g. ofp-(mnitrophenylsulfamyl) -benzoic acid. A sample was purified further byrecrystallization from 50 alcohol. Melting point 245-6" withdecomposition.

21.5 grams (0.0667 mole) of the thus obtained nitro compound wassuspended in 150 ml. of water, and sodium hydroxide solution addeddropwise until the compound went into solution. The solution was weaklybasic. Haney-nickel catalyst was added to the solution and hydrogenationat room temperature was begun. Since there was no appreciable drop inpressure at the end of six hours, the catalyst was filtered off and 4.5gramsof 10% palladium-charcoal catalyst was added. Hydrogenation wascontinued until the pressure drop was 17 pounds (calculated pressuredrop 17.2 pounds). The catalyst was filtered ed. The filtrate wasneutralized with hydrochloric acid, precipitating 17.22 grams of thecrude product. The precipitate was dissolved in dilute hydrochloricacid, treated with char- It will be seen from the above table that theadjuv'ants of this invention are safe, effective and reliable for thepurpose described.

The invention is further illustrated by, but not restricted'to, thefollowing various dosage forms of different compositions foradministration by various routes.

Emample a.-Compressed tablet.10,000 grams of lactose and 100,000 gramsof the adjuvant, para- (meta-aminophenylsulfamyl) -benzoic acid, areuniformly mixed and wetted with suflicient water to permit its readygranulation. 2,000 grams of dried cornstarch, 500 grams of karaya gumpowder, 2,500 grams of talc, and 1,000 grams of calcium stearate areintimately mixed and then mixed together uniformly with the 110,000grams of the mixture of the granulated adjuvant and lactose. The finalmixture is then tableted (using 5 inch die standard curvature punches)yielding 200,000 tablets of 0.58 gram each, and each containing 0.5 gramof the adjuvant.

By replacing the quantity of the adjuvant in the above example by thesame quantity of any other selected adjuvant embraced within the scopeof the general formula above, tablets of the same individual weight andsame content of any of the other adjuvants are obtained.

Measured amounts of the composition of Example a containing any selectedadjuvant, or merely the adjuvant alone, can be filled into hard gelatin,telescopic capsules, each holding 0.5 gram of adjuvant.

Alternately, the selected adjuvant may be homogeneously dispersed in anequal quantity of corn oil, and the composition encapsulated in knownmanner in soft, elastic, sheet gelatin, hermetically sealed capsuleseach containing one gram of the adjuvant-oi1composltion 1 Exampleb.'-Ampul.-10' kilos of the adjuvant, para- (meta-aminophenylsulfamyl)-benzoic acid, are suspended infvery nearly 50 liters of distilled waterand 1368.6"grams of sodium hydroxide are added to help in thedissolution of the adjuvant. 390 grams of monopotassium phosphate areadded and distilled water added to make the volume of solution up to 50liters (pH is about 7.4) The solution is then' filled int ampuls for 5cc. liquid content each, which are then flame-sealed and autoclaved atpounds pressure for minutes.

Example c.--C'ompressed tablet containing penz'cz'ZZin.'l0,000 grams oflactose are mixed with 100,000 grams of the adjuvant,para-(metaaminophenyls'ulfamyl)-benzoic acid, and granulated as inExample-a. 3375 grams of sodium penicillin (1630 units per mg), 2625grams dried cornstarch, 500 grams karaya gum powder, 2500 grams talcandlOGO grams calcium stearate are mixed together in an; atmospherecontrolled at 10% relative humidity 'at 21 C., and then under the sameconditions-mixed with the granulation of the adiuvant and the lactoseand tableted with the same die as in Example 12 yielding 200,000 tabletsweighing 0.6- gram and each containing 0.5 gram of adjuvantand 25,000units penicillin (plus 10% excess). 7

Any other selected adjuvant'may replace the adjuvant of Example 2) inequal amount to obtain tablets of the same weight and same content of'anyof the other adjuvants.

Eivample cl.-Dry filled capsule with penicillin-Underatmospherecontrolled as in- Example c, 25 kilos of the adjuvant,para-(metaaminophenylsulfamyl) -benzoic acid, 850 grams of crystallinepenicillin sodium (as used above), and 150 grams of dried cornstarch areintimately and uniiorm y mixed, and the mixture filled into capsules,.yielding, 50,000; capsules, each holding 0.52 gram ofmixture-containing 0.5 gram of adjuvant and 25,000 units-penicillin(plus. 10% excess).

'Ezcample e. '-Soyt-.elasiic capsule for penicillin-,Uhderhtmosphercontrolled as in Example c, 1.69 kilos of the same crystallinepenicillin sodium are homogeneously dispersed in 48.31 kilos of corn oiland 50 kilosof' the adjuvant, para- (meta-aminophenylsulfamyl)-benzoicacid, similarly dispersed in theoi-l, and the resulting compositionencapsulated in known manner in'soft, elastic, sheet gelatin,hermetically sealed capsules, yielding 100,000 capsules, each holdingone gram'net of the composition and containing 0.5 grain of, adjuvantwith 25,000 units penicillin (plus 10% excess).' I

Example f. Flctme-sealecl ampul filled with pc'niciZZin.l2.5 kilos ofthe adjuvant, para- (meta-aminophenylsulfamyl)-benzo-ic acid, arestirred into very nearly liters of sterile, pyro-- gen-free, distilledwater and 1710.75-grams of sodiumhyd'roxide are added to aid in thedissolution oi-theadjuvant. Then 350 grams of moncpotassiiun. phosphateare added and, under atmosphereconditions, as in Example 0, 169 grams ofthe same crystalline. penicillin sodium are added and stirrcdintosolution and sufficient Water added to bring the-total volume ofsolution to 30 lite'rs. 112cc. of -this.solution are then filled intoeach of the required number of 20 cc. total volume ampul-vials. Thecontents of the vials are then quickly frozen by rotating them in abathof 'riethyl Cellosolve chilled With Dry Ice;to +10. C and;desiccated under high vacuum for' i lfi hoursibythe method and apparatusas in United Statesl 'atent No. 2,353,985 and rubher stoppers insertedneck of eachof; the

containers while the vacuum is still being main-,

units penicillin (plus the 10% excess) and 25% of the adjuvant.

Example o.-Ampul oil suspension with penicillin.3 kilos of USP white waxare mixed into 35.127 kilos of purified peanut oil heated sufficientlyto melt and permit homogeneous dispersion of the white wax. While thismixture is still sufiiciently liquid, and under atmosphere conditions asin Example 0, 10 kilos of the adjuvant,

para-(meta-aminophenylsulfamyl) -benzoic acid,

and 1873 grams 0:" calcium penicillin (734 units/mg.) are added and themixture stirred to homogeneity. Each cc. of the resulting oil suspensioncontains 25,000 units of penicillin (plus 10% excess) and 0.2 gram ofadjuvant. It is put up in flame-seal ampuls containing suitable volumeof the suspension which is as stable as the ordinary penicillin inpeanut oil preparation.

While each of the preceding Examples a through 9 contains its respectivespecific adj uvant, each of them may be prepared with any othersuitable, effective adjuvant, for example, any other adjuvant embracedby the general formula above.

In addition, in those compositions containing penicillin, it isadvisable, in accordance with customary practice, to include an excessof the penicillin, for example, a ten per cent excess over thelabel-claimed quantity in accordance with present practice. An excess ofpenicillin introduces no difficulty save its cost. The penicillin usedmay be any of the forms available for use, such as the calcium, sodium,potassium, procaine, and the hire salts of amorphous or crystallinepenicillin.

The quantity per dose of adjuvant and penicillin will depend upon theblood leveland duration of action required for the particular conditionencountered in each case. An advantageous ratio of adjuvant topenicillin per tablet or capsule is about one-half gram of theselectedadjuvant to 25,000 to 200,000 units of penicillin.

The compositions of the invention may also include an antacid materialsuch as aluminum hydroxide, magnesium trisilicate, trisodium citrate,calcium carbonate, magnesium oxide, or other antacid substances suitablefor administration for the purpose of neutralizing gastric acidity. Theamount of antacid material. is limited only to that Whichis desirable touse in connection with penicillin or Which can be physically incor--porated in a tablet'or capsule of suitable size for administration. V I

As to binders and lubricants used in making the tablets, such materialsas lactose, corn starch, gum karays, talc, calcium stearate, gelatin,ethyl cellulose, mineral oil, propylene glycol, glycerin, and the like,may be included in pro-portions commonly used in preparing tablets ofthis nature.

If. the compositions are produced in the'form of suspensions orsolutions in an oleaginous material, there are available varioussubstances which may be used for this purpose. Corn oil orother'suitable oil is used with advantage.

9 We claim: 1. A sulfamylbenzoic acid which is a member of the groupconsisting of compounds having the general formula:

Q-NB-S 02-0-0 0 0H and their salts, wherein X is a member of the groupconsisting of the nitro and an amino radical.

2. Para-(meta aminophenylsulfamyl) -benzoic acid.

3. A composition suitable for use in conjunction with the administrationof penicillin, comprising an adjuvant which is a member of the groupconsisting of compounds having the general formula and their salts,wherein X is a member of the group consisting of the nitro and an aminoradical.

4. A composition suitable for therapeutic use, comprising penicillin andan adjuvant which is a. member of the group consisting of compoundshaving the general formula:

and their salts, wherein X is a member of the group consisting of thenitro and an amino radical, the quantity of adjuvant and penicillin inthe composition being in the ratio of 0.5 gram of adjuvant to from25,000 to 200,090 units of penicillin.

JAMES M. SPRAGUE. CHARLES S. MILLER.

REFERENCES CITED The following references are of record in the file ofthis patent:

UNITED STATES PATENTS OTHER REFERENCES Reid, Prolongation of PenicillinActivity with Penicillinaise-Inhibitng Compounds," Proc. Soc. Exptl.Biol. and Med., November 1946, pages 438- 443.

Soo-I-Ioo, Activity of Penicillin Combined with Other Anti-StreptococcalAgents, Archives Biochemistry, September 1944, pages 99-106.

Meads, Caronamide and Penicillin, J. Am.

Med. Assoc, November 20, 1948, pages 874-877.

Pratt et al., Antibiotics, Lippincott Co., 1949, pages 112-116. (Book inDivision 43.)

Micewicz-Chemical Abstracts, vol. 22, page 41111 (1928).

Ruggli et al.-Chemica1 Abstracts, vol. 35, column 5473-5474 (1941).

ArntzenChemical Abstracts, Vol. 38, column 61 (1944).

Gilman et a1.-J. Am. Chem. Soc., vol. 69, pages 1537-1538 (1947).

3. A COMPOSITION SUITABLE FOR USE IN CONJUNCTION WITH THE ADMINISTRATIONOF PENICILLIN, COMPRISING AN ADJUVANT WHICH IS A MEMBER OF THE GROUPSCONSISTING OF COMPOUNDS HAVING THE GENERAL FORMULA